The spectral library is hosted by the Mars Space Flight Facility at Arizona State University (ASU) consists of thermal infrared emission spectra (typically 2000 – 220 cm-1) of a variety of geologic materials.

It is open and free, but one needs to register with a valid email address and take the time to learn how to access the data and obtain plots. It is not a trivial task.

Each spectrum comes with descriptive information, sample quality, and a comments field that describes any appropriate, related information.

To quote from the introduction to the library about the sources of data:

“Emission spectra were acquired using a Nicolet Nexus 670 interferometric spectrometer equipped with a CsI beamsplitter and an uncooled deuterated triglycine sulfate (DTGS) detector; the spectral range of the instrument is from 2000 — 220 cm-1 (5 — ~45 microns). Both the spectrometer and the sample chamber/glovebox were continuously purged with nitrogen gas during sample analysis to minimize atmospheric H2O and CO2 which also have absorption features in the 2000-220 cm-1 region of the spectrum. The particulate samples were heated in an oven to 80°C to improve the signal to noise ratio during spectral analysis (this temperature is maintained during analysis by placement of the sample cup on a heater element). The samples were raised into a water-cooled sample chamber that closely approximates a blackbody cavity [Ruff et al., 1997]. A total of 270 scans at 2-cm-1 sampling were taken over ~7 minutes and averaged together by the spectrometer. In the case of a hand sample, active heating during measurement is not possible. Hand samples were taken directly from the oven and placed into the sample chamber and 180 scans were taken over a period of ~5 minutes to minimize the effects of sample cooling. The spectral calibration method is a variation of method 1 of Christensen and Harrison [1993] as described in detail by Ruff et al., [1997].”


References cited above:

“Christensen, P.R., and S.T. Harrison, Thermal infrared emission spectroscopy of natural surfaces: Application to desert varnish coatings on rocks, J. Geophys. Res., 98 (B11), 19,819-19,834, 1993.“Christensen, P.R., J.L. Bandfield, V.E. Hamilton, D.A. Howard, M.D. Lane, J.L. Piatek, S.W. Ruff, and W.L. Stefanov, A thermal emission spectral library of rock-forming minerals, J. Geophys. Res., 105,9735-9739, 2000. {ED NOTE: PDF DOWNLOAD}

“Feely, K.C. and P.R. Christensen, Quantitative compositional analysis using thermal emission spectroscopy: Application to igneous and metamorphic rocks, J. Geophys. Res., 104, 24195-24210, 1999.

“Lane, M.D. and P.R. Christensen, Thermal infrared emission spectroscopy of salt minerals predicted for Mars, Icarus, 135, 528-536, 1998.””Lane, M.D., Midinfrared emission spectroscopy of sulfate and sulfate-bearing minerals, American Mineralogist, in press, 2006.

“Ruff, S.W., P.R. Christensen, P.W. Barbera, and D.L. Anderson, Quantitative thermal emission spectroscopy of minerals: A laboratory technique for measurement and calibration, J. Geophys. Res., 102, 14,899-14,913, 1997.”

Further reference publications related to the work at ASU may be viewed on the ASU website.